Don't the values look kinda small, though? The
datasheet for the AK8975 says that the X, Y and Z components
read from the magnetometer are 13 bits, and the values logged
look a bit smaller than that - 9 bits, tops.
Here are some scaled values:
71.294 201 IMU_MAG_SCALED 698 406 1763
71.394 201 IMU_MAG_SCALED 752 458 1791
71.493 201 IMU_MAG_SCALED 698 458 1959
71.593 201 IMU_MAG_SCALED 792 419 1833
71.792 201 IMU_MAG_SCALED 671 484 1791
71.892 201 IMU_MAG_SCALED 752 536 1847
72.092 201 IMU_MAG_SCALED 658 392 1805
72.190 201 IMU_MAG_SCALED 698 432 1875
72.289 201 IMU_MAG_SCALED 671 484 1819
72.389 201 IMU_MAG_SCALED 738 445 1805
72.588 201 IMU_MAG_SCALED 738 471 1833
72.688 201 IMU_MAG_SCALED 752 406 1819
72.787 201 IMU_MAG_SCALED 698 484 1847
72.887 201 IMU_MAG_SCALED 738 471 1833
72.987 201 IMU_MAG_SCALED 752 484 1903
Not exactly [-1, 1]... Are those fixed point values? Also,
these were taken with the drone on the floor. There seems to
be a little bit of noise, but in the real time plotter, at
least, the magnitude of the noise seems pretty small.
I'm try to read a log from a short flight today, and I
think it would be helpful to look at some documentation for
the telemetry messages - ROTORCRAFT_FP in particular. Is there
any documentation other than the macro definitions in
messages.h?